Yawar Hussain

and 2 more

Unplanned urban growth exerts significant stresses on the underlying aquifers in terms of increasing the groundwater extraction and reducing the surface area for aquifer recharge. This situation has led to a more difficult process in the search for new locations of productive tubular wells, particularly in the Federal District of Brazil. In this region, the groundwater extraction is challenged by fractured aquifers with difficult identification of hydraulic tarps and significant uncertainty in the estimation of recharge potential. The aim of the present study is to optimize the demarcation of new locations of tubular wells by conducting geophysical investigations. In the first stage, based on the information of the physical environment and data from the existing wells, the total exploitable amount of groundwater was calculated. Then Electrical Resistivity Tomography (ERT) was carried out along specific sites, which were selected based on the surficial characteristics. The resistivity values obtained from the dipole-dipole array were inverted and the resultant conducting zones (weathered rocks and fractures) were delineated, which represent possible hydraulic traps where groundwater may exist. Based on the results, the suitability of the selected sites for deep tubular wells installation was prioritized on a linear scale varying from 1 to 5, where 1 is the highest and 5 is the least suitable. Based on this approach, eight new deep tubular well sites were proposed and classified. The study provides a promising framework for investigating groundwater in fractured aquifers.